BENEFICIATION OF ALUNITIC KAOLINS IN BALIKESIR REGION BY CALCINATION AND ITS USE AS POZZOLANIC MATERIAL

Abstract

In this research, the sulphur within the composition of alunitic kaolin of Balıkesir region was removed by calcination processes. During the experiments, three different kaolin samples were used, namely raw kaolin (K) and two types of concentrated kaolins (E and C). While K represents the raw kaolin with a particle size of -38 μm, E represents the under-sieve part which was obtained by screening through a -38 μm sieve after wetting and scrubbing operations. C is the over-sieve part of the operation. The calcination processes were carried out at a temperature range of 500°C and 1000°C. While SO₃ content of calcined kaolins was reduced, the production of metakaolin and its pozzolanic properties were also investigated. The most suitable calcination temperature for metakaolin production was determined by investigating the physical, chemical and mineralogical properties of the products obtained by calcination. After the tests, the production of metakaolin by the calcination of E kaolin at 800°C was found to be higher than that of C and K kaolins. In other word, the production of metakaolin from this kaolin (E) was proven to be possible. Moreover, it was determined that the metakaolin produced (MKE-800) could be used as a pozzolanic material.

Keywords

• Alunitic Kaolin,Metakaolin,Calcination,Pozzolanic Material

BALIKESİR BÖLGESİ ALUNİTLİ KAOLİNİNİN KALSİNASYON İLE ZENGİNLEŞTİRİLMESİ VE PUZOLANİK MALZEME OLARAK KULLANIMI

Abstract

Bu araştırmada Balıkesir yöresi alunitli kaolininin bünyesindeki kükürtün, kalsinasyon işlemleri ile uzaklaştırılmasına çalışılmıştır. Deneylerde, ham (K) ve zenginleştirilmiş (E ve C) olmak üzere üç farklı kaolin kullanılmıştır. K, (-38 μm) boyutundaki ham kaolindir. E, ham kaolinin suda bekletme ve mekanik karıştırıcı ile karıştırılarak 38 μm’lik elekten elenmesi sonucu elde edilen elek altı kısım, C ise elek üstü kısımdır. Kalsinasyon işlemleri 500°C ile 1000°C arasında gerçekleştirilmiştir. Kalsine edilen kaolinlerin SO₃ içerikleri azaltılırken, aynı zamanda metakaolin üretilebilirliği ve bunun puzolanik özelliği de araştırılmıştır. Kalsinasyon sonucu elde edilen ürünlerin fiziksel, kimyasal ve mineralojik özellikleri incelenerek, metakaolin üretimi için en uygun kalsinasyon sıcaklığı belirlenmiştir. Deneyler sonucunda E kaolininin 800°C’de kalsinasyonu ile elde edilen metakaolin oluşumunun C ve K kaolinlerine göre daha fazla olduğu, yani bu kaolinle (E) metakaolin üretiminin mümkün olabileceği saptanmıştır. Ayrıca üretilen bu metakaolinin (MKE-800), puzolanik malzeme olarak da kullanılabileceği tespit edilmiştir.

Keywords

• Alunitli Kaolin,Metakaolin,Kalsinasyon,Puzolanik Malzeme

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